The invention relates to a device for feeding web-shaped packaging material to a packaging machine comprising a spool change device for pulling the packaging material alternately from two spools and for feeding the material to a common conveying track along which a pair of engraving rollers, a pair of conveying rollers, and a cutting device are disposed.
Such a device is used for example for feeding portions of foil for wrapping blocks of cigarettes on cigarette packaging machines.
In this case a problem arises in the embossing process in that the foil has a tendency to coil up after the embossing. So long as a foil web is pulled from a spool and is gripped by a pair of conveying rollers behind the embossing rollers with reference to the running direction, this is not important. However, on changing over from one spool to the other, when the beginning of the new spool runs through the embossing station, the coiling-up effect on the foil hinders further conveying.
Up to the present time this problem has been solved by joining the beginning of the new coil to the end of the old by means of adhesive strips or the like. Thus a device is known in which this problem is solved by disposing two embossing rollers in front of the spool change station of each spool, with respect to the running direction. Splicing, i.e., the joining of the new to the exhausted web is however costly and gives rise to interferences with the packaging process. Moreover, the incorporation of one pair of embossing rollers per spool is costly from the construction aspect, as not only a second pair of rollers but also a drive therefor are required.